


White Mare

by Luna_wolf



Category: Fate/stay night & Related Fandoms
Genre: Backstory, Celtic Mythology & Folklore, Did I mention the trauma, Dysfunctional Family, F/F, Futanari, Morgan is the worst, Rape, Trauma, arthurian legends, supernatural sex
Language: English
Status: Completed
Published: 2018-07-24
Updated: 2018-07-24
Packaged: 2019-06-15 14:44:48
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Rape/Non-Con
Chapters: 1
Words: 3,740
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15415278
Author URL: https://archiveofourown.org/users/Luna_wolf/pseuds/Luna_wolf
Summary: The story of Mordred's conception. To become king, Arturia must undergo a strange ceremony.(CW for graphic sexual assault/rape)





	White Mare

_It was no problem, Merlin insisted. It’s a hassle to seduce a woman who will only bed her husband – a man who has gone to war against you to prevent that very outcome - but there are ways around that. Moreover, seeing as she is the only woman who is capable of bearing the promised heir, it’s really a matter of duty._

_Uther feels no different, but the face that looks back at him from the mirror is that of Igrane’s husband, Gerlois._

_A man’s footsteps echo on the dusty stone of the castle. It was easy to gain entry once he possessed the duke’s appearance. He passes a guard, who nods to him politely. He nods back, and quietly thanks God that the man doesn’t speak to him. A small blonde girl peers at him distrustfully from the darkness, but makes no sound._

_He arrives at Igrane’s bedroom in the dark of the night and kisses her awake. If she notices that the way he kisses her, the way he touches her, is different from the way her husband does, she makes no comment. Her nightgown falls away like a leaf, and her body is more delicious than his wildest fantasies._

_He will leave in the morning. A few hours later, Igrane will be horrified to learn that her husband died in the fighting with the High King’s forces the day before. She knows instantly who visited her that night and collapses with horror, but already the tiny spark that will become the Once and Future King is growing in her womb._

_Merlin is satisfied. It is all going according to plan._

* * *

 

Arturia takes a deep breath and tries to smooth down the front of her tunic. The brocade makes her skin itch – she grew up wearing simple but practical linen and wool, but she isn’t the foster child of Sir Ector anymore. She’s king now, and she has to act like it.

She surveys the scene in the hall. The lesser kings of the land of Britannia have finally gathered here at her bequest. They’re a rough bunch, most of them wearing swords even at this formal occasion. They haven’t bowed down to a high king in over a decade. _But they will now_ , Arturia vows silently.

No one has been murdered yet, which is a good sign. They sip fine Roman wine and mill about, sometimes chatting with old friends, other times giving death glares to enemies from across the room.

She greets them all, the names blurring together in her mind – Lot, Cador, Leodegrance, Meliodas, and many many more. They greet her warmly enough, but cautiously. _Who is this young king_ , their eyes seem to say, _and why should we throw in with him_?

Merlin had been blunt when he’d spoken to Arturia before the evening festivities had begun: “At last, your long-awaited introduction to your subjects! Now, don’t for a moment let yourself forget that they’re all a bunch of jeweled vultures who’d just as soon murder you as look at you.”

Arturia blinked.

“You’re not king quite yet, not until the ritual tonight and the coronation tomorrow. You’ve got to win over these kings, or else your crowned head will end up decorating a spike.” Merlin grins and shrugs, palms facing the sky, as though this is a mildly inconvenient outcome rather than the very way that Arturia’s grand-uncle died.

So here Arturia is, among these hard-bitten kings who had been at war with each other for a decade.

“Your Majesty! There’s someone I want you to meet.” A voice at her side catches her attention. It’s Sir Pelinor, the host of the event. He’s never without a smile, ever eager to please - and Arturia doesn’t trust him farther than she could throw him. He has an obsequious, greasy quality to him. 

Sir Pelinor gestures to a young woman at his side. She is pretty, and would be beautiful if not for the coldness of her features. “This is Morgan, your half-sister. I’m presently fostering her.”

Sister! Those words give Arturia a rush of delight. She’s never known one of her blood relatives before – her mother and father gave her into the care of Sir Ector before she was old enough to remember their faces, and now they are both long dead. But she has a sister. Her heart beats faster and she takes Morgan’s hand in her own. “It would be my honor to invite you into my service at the royal city I’m building, Camelot,” she says to the blonde girl. It sounds like something a king would say, and it would warm Arturia’s heart to have a sister at her side.

Morgan looks at Arturia’s hand as though Arturia has offered her a dead fish, then turns away without a word, vanishing into the crowd. Pelinor, looking nonplussed (he probably thought that this introduction would curry favor with the new king) runs after her. Arturia’s heart sinks.

“Forgive Morgan, she’s always a bit difficult,” another voice says. A tall, sweet-faced girl smiles at Arturia. “It’s an honor to meet you. I’m Guinevere, daughter of King Lot.

“Morgan and I were fostered at the same convent for a while,” Guinevere continues. “She’s, ah, the daughter of Lady Igrane and her first husband, the late Lord Gerlois. So I’m sure you can see why she’s not exactly pleased to meet you.”

“Of course,” Arturia replies with a certainty she does not feel. “It can be difficult to meet a step-sibling.”

“True, and the whole Cornwall affair didn’t help the situation. Gerlois’ body not even cold before Igrane became pregnant with you, if you count nine months back from your birth,” the tall girl shakes her head, then seems to recall who she’s talking to and stammers, red-faced, “I-I’m so sorry! I’m not meaning to insult the memory of your royal parents, please forgive me.”

(In just a few months, this story, which is already in wide circulation around the kingdom, would provide cover for an uprising against the king. According to some, the circumstances of Arturia’s conception meant that the new king is a bastard and therefore unfit for the throne. The claim will have enough validity to draw in the discontented elements of the kingdom and set off a series of conflicts that will occupy the first year of Arturia’s reign. For now, though, these events are still in the distant future.)

Arturia’s stomach lurches. She wishes she could sit down somewhere. She’d never heard the story of her conception before. Had Uther broken Igrane’s marital vows? Had he taken her by force? No one – not Ector, not Merlin – has told her these things about her parentage.

Arturia hides her emotions behind a neutral mask (a kingly skill she’s becoming quite adept at) and focuses her attention on the tall girl, Guinevere. Arturia searches her face, seeking the hidden intent behind these words (a kingly skill that she’s not yet particularly good at). Relaying such a story might be a way to humiliate Arturia, but no, the girl seems sincere in her apology and truly embarrassed at her breach of etiquette.

Arturia thinks again of her fleeting glimpse of her sister, and her heart breaks once more. Morgan’s father had died and then Morgan’s mother had left her to marry Uther after Arturia’s birth. “It seems that Morgan blames me for these events.”

Guinevere frowns. “You weren’t even born yet! You didn’t abuse your kingship or ignore your marital vows.” She huffed. “Don’t take it personally, Morgan’s always like this. One time another girl in the convent criticized her handwriting, so Morgan mixed some dung from the chicken coop in with the girl’s ink.” Guinevere tries to suppress an unexpected giggle, “It’s especially disgusting, you see, because we need to lick our quills before we dip then in the ink.”  

Guinevere can’t hold back a giggle, and her amusement sets Arturia off as well. Arturia only has a second to enjoy this golden moment, laughing with a girl her own age in this stuffy place, before another minor king is at her elbow calling for her attention.

She looks back to Guinevere before she’s drawn back to the crowd, to another discussion about regional fortifications or trade routes. “I thank you for your words, Lady Guinevere. I hope we meet again,” Arturia says to the tall princess, who curtseys shyly. These are the sincerest words she will speak that night. 

Arturia spends the rest of the night moving amongst the lords and petty kings. To those who are uncertain, she offers surety; to those who are fearful, she offers calm; to those in need of guidance, she offers authority. She tries to become the king she says she is. 

* * *

 

Arturia has a little time alone before the ritual, which she savors. She is wearing a short white tunic and white trousers now rather than her original blue. The strange new fleshy appendage between her legs is awkward, and she shifts to try to find a more comfortable way to sit. 

The appendage - Arturia had been concerned she lacked certain necessary qualifications for the ritual, but Merlin had assured her that he could provide a temporary solution to her obvious problem. He had given her a cup of bitter liquid to drink, and sure enough, the cock had sprouted from between her legs.

Arturia pulls back her clothing and looks at it. Really, did men enjoy having these? The thing looks so strange and vulnerable. Given that everyone thinks she’s a boy anyway, it might be easier having one all the time, but she’s happier with her natural equipment.

Still, it’s necessary for the task she must accomplish. She adjusts her clothing and leans back in her chair, watching the setting sun. Takes one deep breath, then another.

Merlin had explained it to her, before he’d given her the cup. “In the old times, before the Romans, it was the duty of the High King to lay with the Lady of the Lake and thereby ensure the fertility of the lands. The Lady is the land, the sovereignty of the earth and the people, and a man must woo her like a lover or the land itself will rise up and reject us.”

He spoke in a strange tone, like a chant. He didn’t sound like the Merlin she knew – unpredictable and wild, but playful at least. 

The meaning of his words unsettled Arturia as well. This kind of duplicity makes her uneasy - how could a person bend two bows or serve two masters? “But the Britons are Christians. It’s one of the things that makes us different from the Saxon invaders. This…what you’re talking about, it sounds like-” 

“It sounds like what everyone else in Britannia does,” Merlin interrupted. “Go to church, say your prayers, but leave offerings at the wells and the crossroads for the old ones. Your official coronation will be performed in the church tomorrow, but we pay our respects to the old gods tonight. I’d bet a phoenix’s tailfeather that the priest who’ll perform your coronation tomorrow will be in attendance at the ritual tonight. Where do you think your name itself comes from? Dea Arto is the bear goddess and the patroness of warriors.” 

“I thought it was from my great-great-grandfather who was a Roman consul by the name of Artorius,” she replied stubbornly, but even as she says it, she knows that Merlin is probably right.  

(She thinks now, alone in her room in her white tunic, about her sister. Morgan. She shares a name with the war goddess who bathes in the blood of the slain, the crow who watches from the crossroads. Igrane certainly had great ambitions for her both of her daughters.) 

Merlin had looked as her with rare solemnity. “I’ll be frank with you, my young king. You intend to assume the throne of a father you’ve never met and rule over a country fractured by war and invasion. You’re going to need all the help you can get, natural or supernatural. Any ritual that lends credence to your claim on the High Kingship is something you should leap at. Besides,” Merlin grinned slyly, solemnity gone, “it should be fun.”

He chuckled slightly when Arturia blushed and sputtered, and with a wicked grin her continued, “Now – you do know how it works, correct?”

Arturia’s face was beet-red. Her cock twitched uncomfortably between her legs, like a puppy catching the scent of a rabbit. “You insert sword into scabbard, it’s pretty straightforward.”

“You’ll be a natural, I’m sure. The Lady gives great gifts to those who earn her favor.” Merlin waggled his eyebrows and clapped her on the shoulder. Arturia tried to contain her embarrassment.

In the present moment, the sun sinks below the horizon. A servant knocks on the door of Arturia’s chambers. It’s time.

* * *

 

The moon is full. The air is warm and filled with the heady scent of spring flowers. Arturia leads the procession seated on a white mare.

The people – the lesser kings and their families – are also dressed in white. They’re signing and laughing, the women scattering flowers. Someone is playing a flute, someone else is playing a drum. They’ve all drunk deeply from the cups of mead passed around before they departed from the castle, but this only partially accounts for their intoxication.

Eros! Desire! It moves all around us and animates us. Arturia knew that tomorrow was what used to be called Beltaine, the festival of fertility. The farmers and common folk in the villages still lit fires and danced and did other things under the cover of night. Generally the Briton nobility were more reserved regarding such events, but the coronation of a new high king called for an appeal to the old powers.

What had Merlin said? “As a man woos a lover”? But she wasn’t a man, even if she had a fleshy appendage between her legs at the moment. She was also realizing that having a cock makes riding a horse rather uncomfortable.

They arrive at the lake. The music and singing die down, as if the stillness of the water imparts a stillness to the gathered crowd.

At their center, Arturia dismounts and stands face-to-face with the white mare. The creature looks at her innocently, perhaps awaiting a gift of carrots. There are worlds in those brown eyes.

In another life, Arturia would have liked to ride her into battle or at tournaments. The animal’s gentle, unruffled disposition would make her an excellent mount. But that isn’t meant to be. A sacrifice must be made to draw the attention of the deities that inhabit this place.

In one smooth stroke, Arturia pulls the knife from her belt and slits the animal’s throat.

A gout of blood stains Arturia’s face and clothing, and the mare dies. Arturia pushes away her own horror and disgust, and in a clear voice calls out. “I am Arthur, High King of Britannia! With this sacrifice, I call upon you. Answer me now.”

And something does.

What rises from the lake is terrifyingly beautiful and not human. It is, however, deeply – even archetypically – female, and Arturia feels her cock harden as firm breasts push against her chest, and a warm mouth seeks hers. She places her hands on the goddess’ hips, which grind against her hungrily.

In a swift motion, Arturia unlaces her britches and let them fall to the ground, exposing her hard cock. Even in this warm moment, she knows better than to take off her shirt, under which her small breasts are firmly bound. Not that any of the assembled nobles are likely to notice; she’s dimly aware that they’re pairing off themselves. Hands removing the lacing of a gown, a mouth kissing an arched neck, a tongue teasing a hard nipple, moans and cries rising. They too are surrendering to the spell of desire, and tonight the bonds of matrimony can be cast aside like useless garments.

She thinks briefly of Igrane and Gerlois (if only they could have had such a chance), before sensation pulls her back into the world. Her cock is so hard it almost hurts, and the goddess has wrapped her legs around Arturia, exposing her sweet wet pussy. Arturia plunges her cock inside.

Arturia’s head snaps back from the pleasure, the heat and wetness caressing her hard member. The goddess screams in delight and rakes her nails across Arturia’s back, leaving bloody tracks, which only causes the young king to thrust harder.

In ordinary life, Arturia is restrained and sensible, keeping her emotions carefully in check. This, however, is not ordinary life – that’s the purpose of ritual - and she hears herself growling like a wild beast as she fucks the Lady of the Lake.

Arturia is no longer sure whether she is lying down, standing, on land, or in the water. The only real thing is the sensation of her cock moving inside the goddess. There is nothing in the world except this all-consuming pleasure.

The Lady of the Lake bucks her hips and cries out suddenly, her tight walls convulsing, and Arturia feels the world around her – trees, lake, kingdom – dissolve into an explosion of white light as she cums.

When Arturia comes back to herself, she is laying on the shore of the lake. She is alone. She hears the sounds – some of them quite loud – of her people in the forest around the lake, but none of them are nearby.

A hand rises up from the stillness of the lake, holding something blue and gold. Arturia is quite sure she felt the touch of that hand not long ago, and she smiles a little. The hand casts the object into the air, and Arturia manages to catch it.

It is a sword and a sheath – a sword sharper and better balanced than any she has ever seen before, and a blue and gold sheath that seems to shimmer in the moonlight. They are uncannily perfect, and she’s certain that they harbor secrets she’ll discover in time. Holding it makes her feel like a part of herself that has long been missing has finally been returned. “Excalibur,” she whispers. She has no idea where the name comes from, but she knows it’s the sword’s.

She gathers her clothes, takes the sword, and begins the long journey back to the castle by herself.  A solitary, sleepy guard lets her in. She makes it to her chambers and falls asleep almost as soon as her head hits the pillow.

She dreams again of fucking the Lady of the Lake. She’s never experienced such radiant pleasure, and yet in this dream the experience is…so much different, so cruder….

Arturia opens her eyes and looks into the face of Morgan. Morgan is straddling her, with Arturia’s cock is buried deep inside her.

Arturia recoils and tries to throw her off. “NO! Morgan, what are you doing?!”  Morgan only laughs in reply and bears down harder.

Arturia tries to grab for her sword, but Morgan holds down her hands. The girl is surprisingly strong, or perhaps Arturia is weakened from her supernatural encounter.

Morgan begins to ride Arturia’s cock, giving a slight whine of enjoyment. Arturia feels her skin crawl with revulsion.

Morgan’s tightness moves up and down Arturia’s cock. The feel of it, the sheer mechanical stimulation of nerve endings – Arturia can’t even call it pleasure, it’s too different from what she felt with the Lady of the Lake - pushes Arturia to the edge. Her orgasm is an ugly thing, wrung out of her. She cums for the second time that night, this time with a cry of agony rather than pleasure.

Only now does Morgan dismount, ignoring the semen dripping down her thighs. Arturia curls onto her side like a wounded animal. Morgan leans down and hisses, “Your father raped my mother and murdered my father. He ruined my family. You were born from lust and death and now you’ll be destroyed by it. You’ll see,” Morgan spits on Arturia’s prone form.

Morgan exits the room, pulling a robe around herself for modesty and leaving behind the shaking form of her sister like a heap of carrion.

Unconsciousness would have been a relief, but Arturia is denied that. Instead, her eyes mindlessly trace the grains of the wood that make up the bedpost. Outside, the stars wheel in the sky and the wind moves through the trees.

It is her first taste of the utter loneliness that will be her lot as a king. No one will come save her. No one can. 

Arturia doesn’t recall falling asleep, but she must have, because she opens her eyes to find Merlin looking directly at her. She realizes she is nude, and pulls a blanket around herself. The idea of anyone else seeing her naked body feels intolerable.

(She does notice that her cock is gone, replaced instead with her original golden-haired vulva, which fills her with relief. Even if her body no longer feels like hers, at least it _looks_ like hers.)

Merlin looks oddly solemn. “What is better, sword or scabbard?”

She stares at him. “What?!”

Merlin repeats himself more slowly, as though she’s a dim-witted child. “What is better, sword or scabbard?”

Arturia thinks for a moment. “The sword, of course.”

“Wrong,” Merlin replies. He gestures at Excalibur in its blue and gold scabbard, lying haphazardly on the floor. “The scabbard is called Avalon. As long as you possess it, you will not die from any wound, nor will you lose any blood.” He wiggles his eyebrows, “I was right, the Lady of the Lake did favor you.”

Arturia looks away. She doesn’t want to talk about what happened last night. Any of it.

Merlin gets, up, stretches, and saunters out, saying something about the need for Arturia to prepare herself for the coronation happening in a few hours. 

Arturia watches him leave with distrust and suspicion. _How much does he know? How much did he plan?_

* * *

 

 Arturia doesn’t know it then, but that night another Pendragon child was conceived in rape and magic and hate. An uncanny image of Arturia, the child would grow unusually rapidly, and her mother would train her relentlessly, brutally, in the arts of combat. Full of anger and rebelliousness, this child – now a knight without peer – would eventually make her way to Camelot, where she would become known as Sir Mordred.

**Author's Note:**

> This may be one of the weirdest things I’ve ever written.
> 
> I wanted to explore Mordred’s conception as well as the cycle of family trauma that seems to plague the Pendragon family. I also wanted to play around with the religious syncretism that characterized 5th-6th century Britain.
> 
> This began as a flashback chapter for _Le Morte D’Arturia_ , but I figured I’d publish it on its own since it’s stand-alone. 
> 
> The history nerd in me feels the need to emphasize that we don’t have any records of Celtic or Romano-British kingship ceremonies exactly like the one Arturia goes through, but rites involving the sacrifice of a horse were common throughout ancient Europe and the Middle East. Emphasis on the sexual prowess of a king also pops up in a number of ancient societies, and hey, I wanted to know why Merlin gave Arty that dick.


End file.
